ES2230882T3 - BIMETHALIAN CYANIDE CATALYSTS FOR THE PREPARATION OF POLYOLETERS. - Google Patents

Abstract

Bimetallic cyanide catalyst (DMC) containing a) one or more compounds of bimetallic cyanide b) one or more complex organic ligands, other than c), and c) one or more alkyl polyglucosides.

Description

Bimetallic cyanide catalysts for preparation of polyethers.

The invention relates to new catalysts of bimetallic cyanide (DMC catalysts) for the preparation of polyethers by polyaddition of alkylene oxides to compounds initiators that have active hydrogen atoms.

Cyanide catalysts are known bimetallic (DMC) for the polyaddition of alkylene oxides to initiator compounds that have active hydrogen atoms (see, for example, documents US 3404109, US 3829505, US 3941849 and US 5158922). The use of these cyanide catalysts bimetallic for the preparation of polyethers, in particular, in comparison with the conventional preparation of polyethers with alkaline catalysts such as alkaline hydroxides, exerts the effect of reducing the proportion of polyethers mono-functional with double terminal links, the called monooles. The polyethers thus obtained can be processed to obtain valuable polyurethanes (e.g. elastomers, foams, coatings). Bimetallic Cyanide Catalysts they are generally obtained by reacting an aqueous solution of a metal salt with the aqueous solution of a cyanide salt metallic, in the presence of an organic complex ligand, by example, an ether. In a typical catalyst preparation, for example, aqueous solutions of zinc chloride are mixed (in excess) and potassium hexacyanocobaltate and then add dimethoxyethane (glime) to the suspension formed. After Filter and wash the catalyst with aqueous glyme solution. obtains an active catalyst of general formula

Zn_ 3 [Co (CN) 6] 2 \ cdot x ZnCl_ {2} \ cdot and H_ {2} O \ cdot z glime

(see document EP 700949).

From documents JP 4145123, US 5470813, EP 700949, EP 743093, EP 761708 and WO 97/40086 catalysts are known of bimetallic cyanide that using terbutanol as a ligand organic complex (alone or in combination with a polyether (EP 700949, EP 761708, WO 97/40086)) further reduce the proportion of mono-functional polyethers with doubles terminal bonds in the preparation of polyethers. Further, using these bimetallic cyanide catalysts reduces the induction time in the polyaddition reaction of the oxides of alkylene with the corresponding initiator compounds, and increases catalyst activity

US 5714428 describes catalysts of bimetallic cyanide which, in addition to terbutanol, contain hydrates of carbon as starch.

The objective of the present invention was provide further improved bimetallic cyanide catalysts, for the polyaddition of alkylene oxides to initiator compounds corresponding, and that presented a catalytic activity increased, compared to known types of catalysts until now. This, by shortening the times of alkoxylation, leads to an improved economy of the process of preparation of polyethers. Ideally, by increasing the activity, then the catalyst can be used in concentrations so low (25 ppm or less) that the expensive one is no longer necessary separation of the catalyst from the product and the product can be used directly for the preparation of polyurethane.

Surprisingly, it was found now that in the Preparation of polyethers, bimetallic cyanide catalysts containing an alkyl polyglucoside as a ligand complex, they have a strongly increased activity.

Therefore, the object of the present invention is a bimetallic cyanide catalyst (DMC catalyst) that contains

a) one or more, preferably a compound of bimetallic cyanide,

b) one or more, preferably, a ligand organic complex different from c), and

c) one or more, preferably, a alkyl polyglucoside.

In the catalyst according to the invention, given the case may be contained d) water, preferably from 1 to 10% by weight, and / or e) one or more water soluble metal salts, preferably, from 5 to 25% by weight, of formula (I) M (X) n, from the preparation of the bimetallic cyanide compounds a). In formula (I), M is selected from the metals Zn (II), Fe (II), Ni (II), Mn (II), Co (II), Sn (II), Pb (II), Fe (III), Mo (IV), Mo (VI), Al (III), V (V), V (IV), Sr (II), W (IV), W (VI), Cu (II) and Cr (III). Zn (II), Fe (II), Co (II) and Ni (II) are particularly preferred. X are same or different, preferably the same and are an anion, preferably selected from the group of halides, hydroxides, sulfates, carbonates, cyanates, thiocyanates, isocyanates, isothiocyanates, carboxylates, oxalates or nitrates. He value of n is 1, 2 or 3.

The bimetallic cyanide compounds a) contained in the catalysts according to the invention are the reaction products of water-soluble metal salts and salts Water-soluble metal cyanide.

Water soluble metal salts suitable for the preparation of bimetallic cyanide compounds a) preferably they have the general formula (I) M (X) n, M being selected from the metals Zn (II), Fe (II), Ni (II), Mn (II), Co (II), Sn (II), Pb (II), Fe (III), Mo (IV), Mo (VI), Al (III), V (V), V (IV), Sr (II), W (IV), W (VI), Cu (II) and Cr (III). Zn (II), Fe (II), Co (II) and Ni (II) are particularly preferred. X are the same or different, preferably, equal and are an anion, preferably selected from the group of halides, hydroxides, sulfates, carbonates, cyanates, thiocyanates, isocyanates, isothiocyanates, carboxylates, oxalates or nitrates. The value of n is 1, 2 or 3.

Examples of water soluble metal salts Appropriate are zinc chloride, zinc bromide, zinc acetate, zinc acetylacetonate, zinc benzoate, zinc nitrate, sulfate of iron (II), iron (II) bromide, iron (II) chloride, cobalt (II) chloride, cobalt (II) thiocyanate, nickel (II) and nickel nitrate (II). Mixtures can also be used. of different water-soluble metal salts.

Water-soluble salts of metal cyanide suitable for the preparation of cyanide compounds bimetallic a) preferably have the general formula (II) (Y) a M '(CN) b (A) c, in which M' is selected from the metals Fe (II), Fe (III), Co (II), Co (III), Cr (II), Cr (III), Mn (II), Mn (III); Go (III), Ni (II), Rh (III), Ru (II), V (IV) and V (V). Very preferably, it is selected M 'between the metals Co (II), Co (III), Fe (II), Fe (III), Cr (III), Go (III) and Ni (II). The water-soluble salt of metal cyanide can contain one or more of these metals. And they are the same or different, preferably the same, and are an alkali metal or metal ion alkaline earth. A are the same or different, preferably equal and are an anion, selected from the group of halides, hydroxides, sulfates, carbonates, cyanates, thiocyanates, isocyanates, isothiocyanates, carboxylates, oxalates or nitrates Both a, b and c are whole numbers, being selected in such a way the values for a, b and c, given the electrical neutrality of the metal cyanide salt; to preferably it is 1, 2, 3 or 4; b preferably is 4, 5 or 6; C preferably it has the value 0. Examples of water-soluble salts of Suitable metal cyanides are potassium hexacyanocobaltate (III), potassium hexacyanoferrate (II), potassium hexacyanoferrate (III), calcium hexacyanocobaltate (III) and hexacyanocobaltate (III) lithium.

Preferred bimetallic cyanide compounds a) which are contained in the catalysts according to the invention, they are compounds of general formula (III)

M_x [M 'x' (CN) y] z,

in which M is defined as in the formula (I) Y

M 'is defined as in the formula (II) Y

x, x ', y and z are integers y are selected in such a way that neutrality is given electric cyanide compound bimetallic.

Preferably

x = 3, x '= 1, y = 6 and z = 2,

M = Zn (II), Fe (II), Co (II) or Ni (II) Y

M '= Co (III), Fe (III), Cr (III) or Go (III).

Examples of bimetallic cyanide compounds a) suitable are zinc hexacyanocobaltate (III), hexacyanoiridate (III) zinc, hexacyanoferrate (III) zinc and hexacyanocobaltate (III) cobalt (II). Other examples of cyanide compounds appropriate bimetallic are derived, for example, from the US document 5158922 (column 8, lines 29-66). Very preferably, zinc hexacyanocobaltate (III) is used.

The organic ligands of complex b), contained in the bimetallic cyanide catalysts according to the invention in principle they are known and are described in detail in the prior art (see documents US 5158922, in particular, column 6, lines 9-65, US 3404109, US 3829505, US 3941849, EP 700949, EP 761708, JP 4145123, US 5470813, EP 743093 and WO 97/40086). Water soluble compounds organic with heteroatoms, such as oxygen, nitrogen, phosphorus or sulfur, which can form complexes with the cyanide compound bimetallic a), are preferred organic ligands of complexes. By example, alcohols, aldehydes, ketones, ethers, esters, amides, ureas, nitriles, sulfides and mixtures thereof are organic ligands of appropriate complex. Water-soluble aliphatic alcohols such as ethanol, isopropanol, n-butanol, isobutanol, sec-butanol and terbutanol are organic ligands Preferred complexes. Terbutanol is particularly favorite.

The organic complex ligand is added, or either, during catalyst preparation, or immediately after precipitation of the bimetallic cyanide compound a). Generally, the organic complex ligand is added in excess.

The conformal bimetallic cyanide catalysts to the invention contain the bimetallic cyanide compounds a) in amounts of 20 to 90% by weight, preferably 25 to 80% in weight, with respect to the amount of the finished catalyst, and the organic ligands of complex b) in amounts of 0.5 to 30, preferably, from 1 to 25% by weight, based on the amount of finished catalyst Bimetallic Cyanide Catalysts according to the invention usually contain 5-80% by weight, preferably 10 to 60% by weight of glycoside, with respect to the amount of the finished catalyst.

The appropriate glycosides for the preparation of The catalysts according to the invention are compounds synthesized from carbohydrates (sugars) and not sugars (agluconas), in which aglucone is linked through of an oxygen atom, by a glycosidic bond, with a C atom of a hemiacetal carbohydrate, forming an acetal full. As the sugar component, monosaccharides are suitable such as glucose, galactose, mannose, fructose, arabinose, xylose or ribose, disaccharides such as sucrose or maltose and oligo- or poly saccharides as starch.

As an unsweetened component, they enter consideration of C 1-30 hydrocarbon residues, as aryl, aralkyl and alkyl moieties, preferably moieties aralkyl and alkyl, most preferably, alkyl moieties with 1 to 30 C. atoms

The glycosides used are the so-called alkyl polyglycosides, which are usually obtained by reaction of carbohydrates with alcohols such as methanol, ethanol, propanol and butanol, or by transacetalization of short chain alkyl glycosides with alcohols fatty with 8 to 20 C atoms, in the presence of acids.

They are especially preferred alkyl polyglycosides with glucose as a unit recurring in the chain, with alkyl chain lengths of C 8 to C 16, and average degrees of polymerization between 1 and 2.

The procedures for the preparation of Glycosides in general are well known and, for example, are described in detail in "Kirk-Othmer, Encyclopedia of Chemical Technology ", volume 4, 4th edition, 1992, P. 916 et seq .; "Römpp, Lexikon Chemie", 10th edition, Stuttgart, New York, 1996; Angewandte Chemie 110, p. 1394-1412 (1998).

Discretionary mixtures of named alkyl polyglycosides previously.

The analysis of the catalyst composition is usually performed by elemental analysis, thermogravimetry or extractive removal of the proportion of alkyl polyglycoside, with the subsequent gravimetric determination

The catalysts according to the invention can be crystalline, partially crystalline or amorphous. The analysis of crystallinity is usually performed by powder diffractometry X-ray

Catalysts are preferred according to the invention that contain

a) zinc hexacyanocobaltate (III),

b) terbutanol and

c) an alkyl polyglucoside.

The preparation of cyanide catalysts bimetallic according to the invention is usually carried out in aqueous solution by the reaction of α) metal salts, in in particular, of formula (I), with metal cyanide salts, in in particular, of formula (II)?) organic ligands of complexes b) that are different from glycoside, and γ) alkyl polyglucoside.

Preferably, the aqueous solutions of the metal salt (for example, zinc chloride, used in stoichiometric excess (at least 50 mol%, with respect to the metal cyanide salt) are first reacted here and of the salt of metallic cyanide (for example, potassium hexacyanocobaltate), in the presence of the organic ligand of complex b) (for example, terbutanol), forming a suspension containing the bimetallic cyanide compound a) (for example, zinc hexacyanocobaltate), water d ), excess metal salt e) and the organic ligand of
complex b).

The organic ligand of complex b) can be in the aqueous solution of the metal salt and / or salt of metallic cyanide, or is immediately added to the suspension obtained after precipitation of the cyanide compound bimetallic a). It proved to be advantageous to mix the aqueous solutions and the organic ligand of complex b) with strong agitation. Usually, the suspension formed with the alkyl polyglucoside c). Here preferably you add glycoside c) in a mixture with water and organic ligand of complex b).

Then, the insulation of the catalyst from the suspension, by known techniques, such as centrifugation or filtration. In a variant embodiment preferred, then the isolated catalyst is washed with a aqueous solution of the organic ligand of complex b) (for example, by resuspension and then new filtration insulation or centrifugation). In this way, for example, they can be removed of the catalyst according to the invention by-products Water soluble, such as potassium chloride.

Preferably, the amount of organic ligand of complex b) in the aqueous wash solution is in a amount between 40 and 80% by weight, with respect to the total solution. In addition, it is advantageous to add something to the aqueous wash solution. of alkyl polyglycoside, preferably in the range between 0.5 and 5% by weight, with respect to the solution total.

In addition, it is advantageous to wash the catalyst more than one time. For this, for example, the first process can be repeated washing But it is preferred not to use aqueous solutions for new washing processes, for example, using a mixture of ligands organic complex and alkyl polyglucoside.

Then, the washed catalyst is dried, if necessary, after spraying, in general, to temperatures of 20 - 100ºC and at pressures in general, 0.1 mbar up to normal pressure (1013 mbar).

Another object of the present invention is the use of the bimetallic cyanide catalysts according to the invention in a process for preparing polyethers, by polyaddition of alkylene oxides to initiator compounds having atoms of hydrogen active.

As alkylene oxides, they are preferably used ethylene oxide, propylene oxide, butylene oxide, as well as their mixtures The synthesis of polyether chains by alkoxylation it can be carried out, for example, with a single monomeric epoxide, or at random or in blocks with 2 or 3 different monomers. More details are detach from "Ullmanns Encyclopädie der industriellen Chemie", English language edition, 1992, volume A21, pages 670-671.

As initiator compounds that have atoms of active hydrogen, preferably compounds with weights are used molecular from 18 to 2000 and with 1 to 8 hydroxyl groups. For example, They are named: ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,4-butanediol, hexamethylene glycol, bisphenol A, trimethylolpropane, glycerin, pentaerythrite, sorbitol, cane sugar, degraded starch or Water.

Advantageously, such compounds are used. initiators that have active hydrogen atoms that were prepared, for example, by conventional alkaline catalysis, to from the lower molecular weight starter compounds, named above, and represent oligomeric products of alkoxylation, with molecular weights of 200 to 2000.

The polyaddition of alkylene oxides to initiator compounds that have active hydrogen atoms, catalyzed by the catalysts according to the invention, in general it is carried out at temperatures of 20 to 200 ° C, preferably in the range of 40 to 180 ° C, most preferably, at temperatures of 50 to 150 ° C The reaction can be carried out at total pressures of 0 to 20 bar Polyaddition can be carried out in the substance or in a inert organic solvent such as toluene and / or THF. The amount of Solvent usually amounts to 10 to 30% by weight, based on the amount of the polyether to be prepared.

The concentration of the catalyst, that under the given reaction conditions a possible Good control of the polyaddition reaction. The concentration of catalyst in general is in the range of 0.0005% by weight and 1% by weight, preferably in the range of 0.001% by weight and 0.1% by weight, most preferably, in the range between 0.001% by weight and 0.0025% by weight, based on the quantity of the polyether to be prepared.

Molecular weights of polyethers prepared by the process according to the invention is found in the range of between 500 and 100,000 g / mol, preferably, in the range of 1000 to 50,000 g / mol, very preferably, in the range between 2000 and 20,000 g / mol.

Polyaddition can be carried out in a way continuous or discontinuous, for example, in a batch procedure or semi-lots

Using cyanide catalysts bimetallic according to the invention, in the preparation of polyethers typically reduce alkoxylation times by 55-85%, compared to the catalysts of Bimetallic cyanide known so far, with terbutanol and starch as ligands. Induction times in the preparation of Polyethers are typically reduced by 25-50%. This leads to a shortening of the total reaction time and thereby to an improved economy of the procedure.

The catalysts according to the invention, by their remarkably increased activity can be applied in concentrations very low (25 ppm and less, compared to the amount of the polyether that it has to be prepared). If the polyethers prepared in the presence of The catalysts according to the invention are used for preparation of polyurethanes (Kunststoffhandbuch, volume 7, Polyurethane, 3rd edition, 1993, p. 25-32 and 57-67), an elimination of the polyether catalyst, without negatively influencing the product quality of the polyurethane obtained.

The following examples illustrate the invention, but they have no limiting character.

Examples Catalyst preparation Example 1 Preparation of a bimetallic cyanide catalyst, using a alkyl-C 8-14-polyglucoside (catalyst A)

To a solution of 4 g (12 mmol) of potassium hexacyanocobaltate in 70 ml of distilled water, with strong stirring (at 24000 rpm) a solution of 12.5 g (91.5 g) is added mmol) of zinc chloride in 20 ml of distilled water. Immediately afterwards, a mixture of 50 g of terbutanol is added and 50 g of distilled water to the suspension formed and then Stir strongly (at 24,000 rpm) for 10 min. Then it is added a mixture of 1 g of alkyl-C 8-14-polyglucoside ®Glucopon 650 EC (Henkel company), 1 g of terbutanol and 100 g of water distilled and stirred (at 1000 rpm) for 3 min. It is isolated solid substance by filtration, then stirred (at 10,000 rpm) for 10 min with a mixture of 70 g of terbutanol, 30 g of distilled water and 1 g of the alkyl polyglucoside mentioned above, and filtered again. Finally I know stir again (at 10,000 rpm) for 10 min with a mixture of 100 g of terbutanol and 0.5 g of the alkyl polyglucoside previously mentioned. After filtration, the catalyst at 50 ° C and normal pressure, until constant weight.

Performance of dried, powdered catalyst: 4.9 g

Elemental analysis, thermogravimetric analysis and extraction:

Cobalt = 12.0%, zinc = 27.0%, terbutanol + alkyl polyglucoside = 33.2%

Example 2 Preparation of a bimetallic cyanide catalyst, using a alkyl-C12-14-polyglucoside (catalyst B)

We proceeded as in example 1, however, as alkyl polyglycoside the alkyl-C12-14-polyglucoside ®Glucopon 600 CS UP (Henkel company) instead of alkyl polyglucoside of example 1.

Performance of dried, powdered catalyst: 4.6 g

Elemental analysis, thermogravimetric analysis and extraction:

Cobalt = 10.8%, zinc = 21.7%, terbutanol = 12.5%, alkyl polyglucoside = 19.0%.

Example 3 Preparation of a bimetallic cyanide catalyst, using a alkyl-C 8-10 polyglucoside (catalyst C)

We proceeded as in example 1, however, as alkyl polyglycoside the alkyl-C 8-10 polyglucoside ®Glucopon 215 CS UP (Henkel company), instead of alkyl polyglucoside of example 1.

Performance of dried, powdered catalyst: 4.2 g

Elemental analysis, thermogravimetric analysis and extraction:

Cobalt = 11.5%, zinc = 22.3%, terbutanol = 9.2%, alkyl polyglucoside = 20.4%.

Comparative example 4

Preparation of a bimetallic cyanide catalyst, using starch (catalyst D, synthesis according to US document 5714428)

To a solution of 4 g (12 mmol) of Potassium hexacyanocobaltate in 70 ml of distilled water is added a solution of 12.5 g (91.5 mmol) of zinc chloride in 20 ml of distilled water, with strong agitation (at 24000 rpm). Immediately then a mixture of 50 g of terbutanol and 50 g of water is added distilled to the suspension formed and then stirred strongly (at 24000 rpm) for 10 min. Then one is added mixture of 1 g of starch (Aldrich company), 1 g of terbutanol and 100 g of distilled water and stirred (at 1000 rpm) for 3 min. It is isolated the solid substance by filtration, then stirred (at 10,000 rpm) for 10 min with a mixture of 70 g of terbutanol, 30 g of distilled water and 1 g of starch and filtered again. Finally, stir (at 10,000 rpm) once more for 10 min with a mixture of 100 g of terbutanol and 0.5 g of starch. After filtration, it dry the catalyst at 50 ° C and normal pressure, up to weight constant.

Performance of dried, powdered catalyst: 6.70 g

Elemental analysis, thermogravimetric analysis and extraction:

Cobalt = 8.2%, zinc = 19.7%, terbutanol = 7.0%, starch = 35.8%

Preparation of polyethers General realization

In a 500 ml pressure reactor, under gas protector (argon), 50 g of initiator are placed polypropylene glycol (molecular weight = 1000 g / mol) and 4-20 mg catalyst (20-100 ppm, with respect to the amount of the polyether to be prepared) and heat to 105 ° C with stirring. It is then added of once propylene oxide (approximately 5 g), until the Total pressure has increased to 2.5 bar. Just add more propylene oxide when an accelerated fall of the pressure in the reactor. This accelerated pressure drop indicates that The catalyst is activated. Next, the oxide is added of propylene remaining (145 g) continuously, at a total pressure 2.5 bar constant. After the complete addition of oxide propylene and 2 hours of reaction time after 105 ° C, eliminate volatile proportions by distillation at 90 ° C (1 mbar) and, at then it cools to room temperature.

The polyethers obtained were characterized determining the OH indices, the contents of double bonds and viscosities

The course of the reaction was followed with the help of time-transformation curves (consumption of propylene oxide [g] versus reaction time [min]). Be determined the induction time from the point of intersection of the tangent at the most outstanding point of the curve of time-transformation, with the prolongation of the baseline of the curve. Indicator propoxylation times of catalyst activity correspond to the time span between catalyst activation (end of induction period) and the end of the addition of propylene oxide. The total time of reaction is the sum of the induction time plus the time of propoxylation

Example 5 Preparation of polyether with catalyst A (100 ppm)

Induction time: 130 min Propoxylation time: Four. Five min Total reaction time: 175 min Polyether: OH index (mg of KOH / g): 29.3 Doubles content links (mmoles / kg): 6 Viscosity at 25 ° C (mPas): 887

Example 6 Preparation of polyether with catalyst B (100 ppm)

Induction time: 160 min Propoxylation time: 70 min Total reaction time: 230 min Polyether: OH index (mg of KOH / g): 29.7 Doubles content links (mmoles / kg): 9 Viscosity at 25 ° C (mPas): 869

Example 7 Preparation of polyether with catalyst C (100 ppm)

Induction time: 170 min Propoxylation time: 120 min Total reaction time: 290 min Polyether: OH index (mg of KOH / g): 28.7 Doubles content links (mmoles / kg): 5 Viscosity at 25 ° C (mPas): 948

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Comparative example 8

Preparation of polyether with catalyst D (100 ppm)

Induction time: 235 min Propoxylation time: 280 min Total reaction time: 515 min Polyoether: OH index (mg of KOH / g): 29.3 Doubles content links (mmoles / kg): 13 Viscosity at 25 ° C (mPas): 859

A comparison between examples 5-7 and the comparative example 8 makes it clear that in the preparation of polyethers with bimetallic cyanide catalysts according to the invention, which contain an organic complex ligand (terbutanol) and an alkyl polyglucoside, in comparison with the preparation with the use of a catalyst bimetallic cyanide containing an organic complex ligand (terbutanol) and starch (described in US 5714428), are they need remarkably reduced induction times and that catalysts according to the invention at the same time possess a strongly increased activity (what is recognized by the times of propoxylation considerably shortened). In addition, the contents of double bonds of the polyols obtained with the catalysts according to the invention are strongly reduced

Example 9 Preparation of a polyether with catalyst A (20 ppm)

Induction time: 350 min Propoxylation time: 355 min Total reaction time: 705 min Polyether: OH index (mg of KOH / g): 29.6 Doubles content links (mmoles / kg): 6 Viscosity at 25 ° C (mPas): 1013

Without removing the catalyst, the content of Metal in the polyol amounts to: Zn = 5 ppm, Co = 2 ppm.

Example 9 shows that the new catalysts bimetallic according to the invention, due to its activity remarkably increased, in the preparation of polyethers can be added in quantities so low that one can do without separation of the catalyst from the polyol.

Claims (7)

1. Bimetallic Cyanide Catalyst (DMC) that contains

to)

one or various bimetallic cyanide compounds

b)

one or several complex organic ligands, other than c), and

C)

one or various alkyl polyglycosides.

2. Bimetallic cyanide catalyst according to claim 1, additionally containing d) water and / or e) a salt water soluble metal. 3. Bimetallic cyanide catalyst according to claims 1 or 2, wherein the bimetallic cyanide compound It is zinc hexacyanocobaltate (III). 4. Bimetallic cyanide catalyst according to one of claims 1 to 3, wherein the organic ligand of complex is terbutanol. 5. Bimetallic cyanide catalyst according to one of claims 1 to 4, wherein the catalyst contains from 5 to 80% by weight, preferably 10 to 60% by weight of a glycoside 6. Procedure for the preparation of a bimetallic cyanide catalyst according to one of the claims 1 to 5, which includes the steps:

i)

reaction in aqueous solution of

α)

metal salts with salts of metallic cyanide

\beta)

organic complex ligands which are different from alkyl polyglucosides, Y

γ)

a alkyl polyglycoside

ii)

insulation, washing and drying of catalyst obtained in step i).

7. Use of one or several cyanide catalysts bimetallic according to one of claims 1 to 5, for the preparation of polyether polyamides of alkylene oxides a initiator compounds that have hydrogen atoms assets.